When it comes to sports shoes, the bouncier you get, the better. Whether you’re running or playing basketball, having the shoes conserve and rebound the energy you put in every step means conserving more of your energy for other things. Of course, you also have to balance bounciness with durability, a problem that shoe designers and engineers constantly try to solve with new technologies and sometimes unusual materials.

Japanese sportswear company Mizuno has one such technology that it will be flaunting at the Osaka World Expo 2025 in April this year. More than the brand’s bold claims of bounciness and softness, the Mizuno Enerzy will probably be most remembered for its rather unusual and perhaps a little disturbing design, with soles filled with spheres that look like bubbles or some otherworldly creature. Perhaps it’s for the best that it will come in black instead of the original design.

Designer: Mizuno

Some have likened them to caviar because of their red spherical shapes, while others have compared them to eyeballs. In fact, one of the designs for these rather odd sneakers does have red eyeballs beneath the blue upper, just like Osaka Expo’s equally odd mascot, Myaku-Myaku. The similarity is just coincidental, of course, but the perfect match-up feels almost fated.

The bubbly outsole of the Mizuno Enerzy sneakers immediately conjures up images of bouncy things like balls and, well, some bubbles, which is probably the intention behind this quirky design. It’s supposed to be a shoe that promises the ultimate bounce and energy return, though funnily enough, it’s not because of those soles. Mizuno Enerzy technology, particularly the Enerzy Core, is actually found in the midsole.

Mizuno Enezy Core, according to the official marketing spiel, is the company’s bounciest and softest midsole material yet. It is claimed to be 293% softer (hopefully not a typo), and provides 56% more energy return, giving you more bounce at every step with less effort. If you indeed feel those effects, you probably won’t mind how the shoes look, especially if you gain a bit of fame from it. Unless, of course, you happen to have a case of trypophobia or a similar aversion.

The original red sole and black upper color scheme of the Mizuno Enerzy was supposed to just be a concept model meant to symbolize that bounciness. For better or worse, Mizuno has decided to actually bring the shoes to the world, though in an all-black scheme that almost minimizes the shocking impact of those small spheres. If you feel like you’re missing out on the Osaka Expo connection, however, the insoles still have that alien-like mascot, though wearing the shoes will probably make it feel like you’re stepping and squashing the poor thing.